The present invention relates generally to the art of forming coils of conductive wire and more particularly to the concurrent forming of a plurality of such coils of wire about a rotating coil form.
A wide variety of techniques for winding coils are known. In some cases, one end of a wire is fastened to a coil form and then that form is rotated to form the turns of wire on the coil form. In other cases, the wire is dispensed from a so-called flyer with that flyer rotating about a coil form to generate the wire turns thereon. In some cases, wire is dispensed directly to a coil form where that wire will remain when the coil is utilized, while in other cases an intermediate coil form initially receives the wire with the coil thereafter being transferred to its final location. The present invention is concerned with winding schemes where the coil is generated about a coil form on which the coil will remain throughout its useful life, however, the manner in which the turns are generated, that is by a rotating flyer or by revolving the coil form, is immaterial to the present invention.
An exemplary environment in which the present invention finds particular utility is the production of ignition coils, such as secondary coils employing a relatively large number of turns of relatively fine wire which are frequently formed on a tubular insulator and often employ winding layers separated by insulating paper or the like.
The prior art approach to winding such exemplary ignition coils was to provide a winding tube of insulating material, such as cardboard, about which a plurality of such coils were to be formed, and attaching individual lead wires to the start lead of the wire for each such coil with the lead wires threaded through holes in the winding tube, whereupon the tube was rotated to simultaneously form several coils and thereafter the tube sectioned to separate individual coils. An alternate approach to the individual lead wires was simply to bring the magnet wire directly out of the coil. In either case, the wires can become tangled, broken or cut off while handling the assembly or while cutting the tube to separate individual coils. Coils formed by this general technique are known in the art as stick wound coils.